MobiKa - Low-Cost Mobile Robot for Human-Robot Interaction

One way to allow elderly people to stay longer in their homes is to use of service robots to support them with everyday tasks. With this goal, we design, develop and evaluate a low-cost mobile robot to communicate with elderly people. The main idea is to create an affordable communication assistant robot which is optimized for multimodal Human-Robot Interaction (HRI). Our robot can navigate autonomously through dynamic environments using a new algorithm to calculate poses for approaching persons

Due to demographic change in the coming years, the number of elderly people will increase in most industrialized countries. Robot technology can help these people to live self-determined and independent in their homes as long as possible and to reduce the need for ambulant or stationary care, e.g. by providing means of communication, detecting anomalies and emergencies, guiding people and fetching objects. Service robots can also support other people with reduced mobility such as rehabilitation patients.

Private households are highly dynamic enviroments which are primarily designed for humans. Therefore a mobile robot has to cope with narrow passages and needs a design that supports safe HRI. To be affordable, robots need to be availiable at low cost, but offer at the same time considerable functionality.

In this paper, we introduce MobiKa (Mobile Communication Assistant) depicted in Fig. 1. Our vision is to solve the aformentioned issues by developing an affordable multi-purpose mobile service robot focusing on communication. MobiKa can navigate autonomously within a pre-mapped environment. For Human-Robot Interaction, MobiKa is able to approach robustly the user. MobiKa is easy to use, even for non-technical users. With the use of functional hardware design and modular software architecture, we provide a highly adaptable robot platform.

MobiKa is designed as a mobile communication assistant. While designing the robot, the main idea was to create an affordable system optimized for Human-Robot Interaction. Therefore we chose a functional design which helps us to reduce the price and illustrates, that the robot’s capabilities are far away from that of a human. To make it affordable, we based the design on open-source software and low-cost hardware.

The goal of the development was to cover functions such as:

General communication tasks via multi-modal interfaces (speech and visual)

Entertainment functions (games and services on display, activating the user)

Reaction to users falling; connection with stationary sensors and networks to allow detection of medical emergencies and contacting an external service provider (robot guides to fallen person)

Reminding of appointments and taking medication

Telepresence and telemedicine

Simple transport tasks (user places objects on the robot)

Guiding persons

Open infrastructure to third-party apps, e.g., for medical services

With these functions, MobiKa can support elderly persons to stay independent and live longer in their homes. It can also assist rehabilitation patients so that they can return to their normal every-day routine earlier.

MobiKa is built on a compact mobile base in which the main components reside. The dimensions of the robot were derived from the intended user interaction; to interact with standing persons, MobiKa needs a minimum height of

1.1m.

To also allow interaction with sitting and lying persons, the screen needs to be adjustable in height. Therefore a belt-driven linear axis was designed, that allows adjusting an Android tablet to the pose of the user. Length and width and also mass were kept as low as possible, which required to concentrate the mass close to the ground to maintain stability during travel.